Clutch control mechanism



Dec. 12, 1939.

5-, JOHNSON. JR CLUTCH CONTROL MECHANISM Filed Sept. 17, 1937 ZSh'eets-Sheet 1 c. ,1939. s. JOHNSON; JR 3,48

' CLUTCH cqhm'nbl. MECHANISM Filed Sept. 17, 1937 2 Sheets-Sheet 12 Patented Dec. 12 1939 Stephen Johnson, In, Pittsburgh, Pa., assignor to I Bendix-Westinghouse Automotive Air Brake Company, Pittsburgh, Delaware Pa a corporation of Application September 17, 1937, Serial No. 164,3}?! 11 Claims. (Cl. 192 -35) This invention relates to controlling systems, and more particularly to systems for controllin thepower transmission mechanism of vehicles.

In motor vehiclesof the type having a gear set and clutch, it has been found desirable to provide devices for obtaining a relatively slow and smooth engagement of the -clutch after establishment of a desired gear ratio without relying on the skill of the operator. Such devices have been more particularlyof the type where clutch engagement has been retarded by a dash pot or piston and cylinder arrangement operatively connected to the clutch throw-out mechanism and having, for example, a restricted port connecting the cylinder to atmosphere. J

Mechanisms of the above type have been operative, however, with the gear set in both neutral' and gear-engaged positions, and have accordingly precluded the use of the well known method 0 of double-clutching by the operator to obtain a smooth shift from one gear ratio to another, it being impossible with such mechanisms to engage and disengage the clutch with suflicient rapidity to accomplishthe desired double-clutch- 5 ing action when the gear set is in neutral.

It is accordingly an object of the present in-. vention to provide a control system for permitting double-clutching on vehicles equipped with control devices which act to retard clutch engagef 0 ment.

A further object, is to provide mechanism for rendering the clutch engagement retarding means inefiective, when the gear set is in neutral.

Another object is to provide means for render- 5 ing the clutch, engagement retarding feature efiective or inefiective without necessitating the use of any additional controls by the operator. 7

Still another object of the invention is to provide interconnecting means between a gear set 1 control system and a clutch controlsystem'for automatically controlling the action of the clutch engagement retarding mechanism.

Yet another object is to provide fluid pressure means controlled by a gear set control member in connection with a power actuated clutch mechanism for rendering the clutch retarding device ineffective when the control member is in neutral position. f

A still furthe'robject is to provide means operated by a gear set ratio control member to render the clutch retarding device operative or" inopera tive, dependent on the gear ratioselected and .-established by .the operation of the control member. I I v Other novel objects and features of the invention will be more readily apparent from the following detailed description when taken in connection with the accompanying drawings, itbeing expressly understood,'however, that the drawings are for purposes of illustration only and are not 5' designedas' a definition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawings, wherein similar reference characters refer to similarparts throughout the several views:

Fig. 1 is a diagrammatic view, partly insection", illustrating an automotive vehicle power transmission control mechanism constructed in accordance with the principles of the present in- 16 vention;

Fig. 2 is a diagrammatic view, partly in sec tion, illustrating in connection with a power transmission control system a modification of the invention; 20

Fig.3 is a-plan' view, partly in section, illustrating a portion of the mechanism shown in Fig.2;

Fig, A is an axial view, partly in section, taken along lines 44 of Fig. 2, and

. Fig. 5 is a diagrammatic view, partly in section. illustrating a modification of the invention .in connection with a fluid pressure operated gear set. control mechanism.

Referring more particularly to Fig: 1, a form of the present invention is disclosed, therein as being associated with a motor vehicle 'power transmission control mechanism comprising in general a manually operable gear ratio control member 5, which may be supported for universal movement as by means of a ball and socket joint 6 and adapted to engage at its lower end a gear shifting member I through the medium .of a transverse slot 8 therein,'and a, clutch control element 9 adapted to be actuated by a fluid motor lll associated with a fiuid pressure reservoir Ii 40 through a pressure control valve i2 which may be manually operated, thus providing means whereby the operator can easily and efficiently control the shifting of the gears and disengagement and v engagement of the clutch, as will be more fully described hereinafter. I a I w The clutch control 'valveyi2 is preferably 'of the well known self-lapping type and may be constructed in accordance with the principles forth in the application of William J. Andres, Serial No. 13,008,. filed March 25, 1935, whichhas matured into Patent No. 2,141,678 dated Decen'1- ber '27, 1938. As disclosed in the above referred the latter being acted on in one direction by an outside force exerted by the operator to cause movement of the member in a corresponding direction suflicient to connect a source of fluid pressure to an actuator by closing the exhaust valve and opening, the intake valve, and being acted on in the other direction by the pressure of fluid in the actuator whichopposes the outside force and tends to move the pressure responsive member in a reverse direction to allow closure of the intake valve, thus maintaining a pressure in the actuator proportional to the outside force exerted by the operator. A resilient member such as a graduating spring is interposed between the pressure responsive member and a suitable plunger connected to an operator controlled pedal, this spring serving to render the valve self-lapping in a manner well known to those skilled in r the art.

In the instant application, the valve I2 of the type described is shown as being provided with a plunger |3 which may be operated in the manner hereinbefore described as by means of a roller l4 carried by a pedal member |5 pivotally mounted on a portion of the valve l2 by means of pivot pin I6 and is operative on downward movement of the pedal member I5 to connect the fluid motor III to reservoir II by means of conduits I] and I8. Upward movement of the pedal operates the mechanism of valve |2 to disconnect the fluid motor from reservoir II and to connect it to atmosphere through conduit l1, and exhaust passage l9, a suitably restricted exhaust port being formed in one end of a fitting 2|, which latter forms a continuation of the exhaust passage l9.

The fluid motor ID as shown in Fig. 1 may 1 comprise a cylinder 22 having a piston 23 slidably mounted therein and being operatively connected to the clutch control element 9 by means of va piston rod 24 pivotally connected to a lever 25 by a pivot pin 26, the lever 25 having a connection with the element 9 through a rotatable shaft 21. A spring 28 may be interposed between the piston 23 and the end cover 29 of the cylinder for normally maintaining the piston at the left end of the cylinder, the vehicle clutch being engaged when the parts occupy this position. It will thus be apparent from the above that admission of fluid pressure to the motor I0 through conduit U will move the 'piston 23 to the right, compressing spring 28 and causing clutch-disengaging movement of the element 9 in a clockwise y direction about shaft 21, while the release of fluid pressure from the motor through conduit l1 and valve |2 will result in clutch-engaging movement of the piston 23 under the action of the compressed spring 28.

From the foregoing description, it will be understood that operation of the clutch control valve pedal I5 downwardly will cause disengagement of the clutch due to the admission of fluid pressure to the motor In and the resulting clockwise movement of the clutch control element 9, while release of the pedal will cause a relatively slow clutch-engaging movement of the element 9 in the reverse direction because of the restric tion imposed on the exhaust of fluid pressure from the motor II] by the restricted port 20, the size of this port being so chosen as to result in smooth and efficient engagement of the clutch at a predetermined rate regardless of 'a quick and smooth engagement of the clutch is neither desirable nor necessary when certain gear ratios, are engaged or when the gears are neutralized, and, in the embodiment of the invention shown in Fig. l, interconnecting means are provided between the clutch and gear ratio control systems for rendering the restricted exhaust port associated with the clutchcontrol valve ineffective when the gears are neutralized and for rendering it effective when a gear ratio is established, this being accomplished automatically and without necessitating the use of additional controls by the operator. In this embodiment of the invention, such interconnecting means may comprise an auxiliary control valve 30 having a body 3| and a valve member 32 rotatably mounted therein and adapted by means of a relatively unrestricted passage 33 in alignment with a similarly unrestricted passage 34 formed in the valve body, to permit a free passage of fluid pressure through the valve. The left end of the valve passage 34 is connected to the fitting 2| associated with clutch control valve l2 by means of a comparatively large conduit 35 and the right end is open to atmosphere, the valve parts being maintained in the relationship shown by means of a lever 36 operatively connected with the valve member 32 and connected to the gear ratio control member 5 by a rod 31 and pivot pins 38 and 33, the control member i being shown in neutral position. It is to'be noted that, with the member 5 in the position shown, the exhaust of fluid pressure from the motor I0 is substantially unrestricted and passes freely from the valve l2 to atmosphere through passage l9, fitting 2|, conduit 35, and passages 33 and 34 of the valve 30, resulting in a rapid rate of clutch engagement on release of pedal l5 by the operator. L

In starting a vehicle equipped with this invention in low gear, the operator, after depressing the pedal l5 to move the element 9 to clutchdisengaged position by virtue of the resulting operation of control valve l2 in supplying fluid under pressure to the fluid motor III to move the piston 23 to the right, may, for example, move the gear set control lever 5 in a counterclockwise direction to engage a low gear ratio, resulting in gear ratio-engaging movement of the gear shifting member I to the right, the latter being guided for'longitudinal movement as by means of a rod 40 attached thereto and slidably mounted in guide brackets 4|, which may be supported by a gear set casing or cover, not shown. Such movement of the member I will result in engagement of low gear in a well known manner, and the parts are so arranged that movement of the control member 5 as described will also move the valve member 32 to a position where the passage 33 of the valve member will no longer register with the passage 34, and the auxiliary valve 30 will thus out off communication between the exhaust passage IQ of the clutch control valve l2 and the atmosphere and render the port 20 of fitting 2| effective to restrict the exhaust of fluid from the motor III. The low gear being engaged, the operator has only to remove his foot from pedal 5 to allow' the escape of fluid pressure from the motor I0 through the conduit l1, valve l2, passage is, fitting 2| and restricted port 20 at a predetermined and relatively slow rate' to accomplish a smooth engagement of the clutch and a uniform acceleration of the vehicle irrespective of the degree of skill exercised by him in controlling the pedal. As heretofore stated, it is often desirable to double-clutch during a shift .position, the valve 30 will again be closed and the restricted exhaust port 20 will effectively re- 'tard the release of fluid pressure from the motor III to insure engagement of the clutch in the manner described. It will be readily apparent from the foregoing description that, to effect the well known double-clutching operation in a quick and eiiicient manner, it is necessary that the momentary engagement and disengagement of the clutch when the gears are neutralized occur within a small period of time, and applicant's auxiliary control valve interconnected with the clutchand gear shift controls provides a novel and simple means for attaining this end, and at the same time allows the use of the automatic clutchengagement retarding feature when the gears are in engaged position.

It is sometimes desirable in systems of the above type to have engagement of the clutch automatically retarded only on establishment of one of a plurality of gear ratios, and, with reference more particularly to Fig. 2 of the drawings in conjunction with Figs. 3 and 4, a modified form of the present invention is shown, wherein a plurality of gear shift members or forks 1 having transverse slots 8 are shown as being carried 2 by longitudinally slidable shift rods 48. A rod 42 suitably mounted in a casing 43 for oscillating and longitudinal movement with respect thereto is provided with a crank portion 54 operatively connected with the universally mounted control lever 5 as by means of a bore formed therein and a ball-like portion 8a formed on the lower end of lever 5, the rod 42 having attached to theleftend thereof a member 48 adapted to selectively engage the slots 8 of the gear shift forks 1 at its lower end and to move the selected fork to gear-engaged position in response to a corresponding movement of the gear control lever 5. The clutch control system in Fig. 2 is sub-. stantially the same as that shown in Fig. 1 hereinbefore described, the control valve 12 having restricted exhaust port 28 associated with exhaust fitting 2| and unrestricted exhaust conduit 35 connecting the fitting with the auxiliaryconnection to atmosphere through conduit 35,

valve 30 and an exhaust pipe 53 connected therewith. To engage lowgear for instance, the lever 5 as viewed in Fig. 4 may be shifted to the right,'.

rotating the rod 42 and member 48 so that the latter selects the lower shift fork 1 as viewed in Fig. 3, and subsequent movement of lever 5 to" the right as viewed in Fig. 2" will move the rod 42 and the selected shift fork-l to the left to establish the low gear ratio. At the same time,

.a valve shifting flnger 54 attached to they rod 42 is shifted as shown in the dotted lines in Fig. 4 to engage and move-valve 'rod 48 to the left by -means of' a collar rigidly attached thereto.

thus closing the valve 30 when low gear is engaged and providing for a smooth clutch engagement on subsequent release of the clutch pedal by rendering the restricted exhaust port 20 effective in the manner heretofore described. It will be apparent from Fig. 2, however, that, if lever 5 is movedto the left from neutral position, the

rod 42, member 46 and shift fork I will be moved to the right to engage another gear ratio, but that there will be no corresponding movement of the'valve rod 48 to the right, the finger 54 merely moving to the right from collar 55 without imparting movement thereto, and it is further noted with reference to Figs. 3 and 4 that the other shift forks I may be selected and moved to gearengaging position without corresponding opera- W tion of the valve 38, the valve being moved to closed position to render the restricted exhaust port 20 effective only when low gear is engaged. Applicant thus has provided novel means for selective engagement and operation of the auxiliary valve 30 for providing automatic control of clutch engagement when starting the vehicle in low gear, the automatic control being ineffective, when the gear set is in neutral or when other gear ratios are engaged, to the'end that, after the vehicle has been started in low speed, the automatic control mechanism will thereafter be rendered ineffective and' the other gear ratios may be readily engaged in an efllcient manner by the use of the well known double-clutching method hereinbefore described.

Referring now to' Fig. 5 of the drawings, another embodiment of the invention is illustrated wherein applicant's novel clutch control mechanism is used with a fluid pressure operated gear shift control system which may beof the type more fully disclosed in Roger H. Casler et al. ap plication Serial No. 697,193, filed November 8, 1933. Such a system is shown as comprising a member 56 oscillatable to select and longitudinally movable to establish desired gear ratios, and having fluid motors 51 and 58 including suitable pistons and piston rods 59 and 60 in engagement with member 55 forrespectively imparting oscillating and longitudinal movement to themember. An operator control unit 5| is provided, having a pair of valves operable selectively in response to movement of the control lever 62 upwardly or downwardly, as viewed in Fig. 5,'for controlling the flow of fluid pressure to selector cylinder 5-! .through conduits 63 or 64, and another pair of valves operable on movement of the control lever to the right or left for controlling the flow of -fluid pressure to a double acting relay cylinder 85 by means of conduits 66 or 61, the valves having their intake valves connected to the fluid pres-' siu'e reservoir II by a common conduit 68. The

relay cylinder 55 has a piston" and piston rod 69 normally held in mid position by springs 15- as shown, and operative by virtue of the rocker arm Illa connected thereto on movement in either,

direction from this position to actuate a dual.

control valve 1| carried by the piston rod to for connecting reservoir H to the motor 58 through a supply conduit 12 leading from the reservoir II to the valve and conduits 13 or '14 respectively,

depending on whether the relay piston and piston rod ismgved toward the left or toward the right be understood that movements, of the control lever 62 in the various slots of the valve unit 6! will cause corresponding movements of the shift forks I through their respective connections with fluid motors 5'! and 58.

A fluid pressure clutch control system of the type heretofore described is shown for controlling the clutch control element 9 by means of fluid motor i and control-valve l2, the latter acting to control the flow of fluid pressure from reservoir II to the fluid motor through conduits l1 and I8 and having an exhaust conduit 15 for connecting the exhaust port thereof to a fluid pressure controlled. auxiliary valve device I8. The latter includes a casing. 'Il having chambers 18 and 19 connected to atmosphere by restricted and unrestricted ports 88 and 8| respectively, there being a valve seat 82 formed at the right end of chamber 18 adapted to receive a ball valve 83. A bore 84 in casing 11 is closed at the rig-ht end by a cover 85 and has a piston 86 slidably mounted therein for forcing the ball valve 83 against its seat through the medium of a spring 81 and a guide member 88, the spring being interposed between the piston and guide member as shown. The spring is normally free from compression with the parts in the position shown so that the slightest pressure in chamber 18 will be sufficient to move the valve from its seat and.

determined by the dimensions of the spring and the position of the shoulder in the casing, thus holding the ball valve against the seat 82 with a force corresponding to the degree of spring compression for preventing-the passage of fluid from chamber 18 to chamber 19 and causing fluid under pressure in chamber 18 to escape through the restricted exhaust port 88. It will thus be seen that auxiliary valve means operable by fluid pressure are provided for permitting either an unrestricted exhaust of fluid from the clutch motor or a restricted exhaust of fluid therefrom, dependent on the actuation of the valve 83 by the piston 86. I

In the embodiment of the invention shown in Fig. and described above, fluid under pressure is conveyed from the control valve unit 6| to the piston 86 through conduits 66 and 90 or 61 and 9!, a double check valve 92 of well known design, conduit 93 and port, 94 in cover plate .85. Conduits -9i) and 9| are provided with adjustable valves 95 for controlling the rate of fiow of fluid under pressure to and from the auxiliary valve device 16 in order that operation of the auxiliary valve I6 may be properly synchronized with that of the gear shift control system. It is therefore apparent that, if the control lever 82 is moved to operate the control valves of unit 61 and supply fluid under pressure to the relay cylinder for actuating the motor 58 through the operation of dual valve 1| to establish a given gear ratio, conduits 66 or 81 will be energized, dependent on whether the control lever is moved to the right or to the left as viewed in Fig. 5, with a resulting energization of conduit 93 and movement of piston 86 to the left to close the valve 83. Since pressure must be maintained in the relay cylinder .65 to hold the gears in engaged position, it follows that the conduit 93 will be energized whenever a gear ratio is engaged, thus rendering 'sition will cause the valves of control valve unit iii to exhaust fluid pressure from the relay cylinder 85 as well as from the auxiliary valve device 16 by way of port 94, conduit 93, double check 'valve 92, and conduits 90 and 66 or 9| and 61,

thus removing the force of spring 81. from ball valve 83 and rendering the large exhaust ports 8| of valve device 16 effective to exhaust fluid pressure from the clutch motor l0 through the control valve [2 at a rapid rate on release of the latter by the operator and permit the desirable double-clutching action heretofore described when the gears are in neutral position. The valve device I6 may also be actuated by fluid pressure from the dual valve II, in which case the conduits 96 and 91 shown in dotted lines and respectively connecting the left side of double check valve 92 with conduit 13 and the right side with the right end of cylinder 58 -may replace conduits 90 and 9| without materially changing the mode of operation of the invention.

While several embodiments of the invention have been shown and described with some particularity, it is to be expressly understood that the scope of applicants invention is not to be limited thereby, except as defined by the appended claims.

What is claimed is:

1. In a control mechanism for vehicles having a gear set and clutch, fluid pressure operated control means for the gear set, a fluid motor for actuating the clutch, valvular means including a restricted exhaust port and a relatively unrestricted exhaust port for controlling the flow of fluid pressure from said motor, and means controlled by the pressure of the fluid in said first named means for rendering said unrestricted exhaust port effectivewhen the gear set is in neutral.

2. In a control system for power transmission mechanism having a gear set and clutch, fluid pressure operated control means for said gear set, a fluid actuator for said clutch, valvular means including a fixed restricted port for releasing fluid from said actuator at a predeterd mined rate, and means including 'a connection with said valvular means and controlled by the pressure of the fluid in said first named control meansfor actuating the valvular means for releasing fiuid from said actuator at a rate greater than said predetermined rate when the gear set is in neutral.

In a control mechanism for vehicles having a gear'set and clutch, fluid pressure operated control means for the gear set, a fluid pressure actuator for the clutch, means including. a restricted port and a relatively unrestricted port ments of said element, means for retarding 1 independent oi the position thereof,.said means lished.

clutch-engaging movements of said element at a p edetermined rate independent oi. the position-Z thereof. andfluid pressure operated means con-. trolled by the pressure 0'! the fluid in said flrst named means for rendering said retarding means inefl'ective when a neutral gear relation is estab- 5. In a control system for vehicles having a gear set and clutch, fluid pressure control means for said gear set, a clutch control element, means being controlled by the pressure of the fluid in said flrst named means for eflecting an increase in the rate of clutch-engaging movement of said element when the gear set is in neutraL,

- 6. In a control-mechanism for a gear set and clutch, a source of fluid pressure, a fluid pressure system including an actuator for controlling the gear set, a fluid motor for operating the clutch, valvular means for controlling the flow oi fluid pressure to and ,from said motor, and valvular means responsive to the pressure of fluid in said system for restricting the flow of fluid pressure from said motor through said valvular means.

I. In a control mechanism for a gear set and clutch, a source of fluid pressure, a fluid pressure system for selecting and establishing a desired gear relation, a clutch control element, a fluid motor for actuating saidelement, valvular means at a predetermined rate, a fluid pressure operated 7 gear set movable to 'eflect engagement and disengagement of desired gear ratios, and means associated with said-valvular means and operable in response tofluid pressure during movement of said'gear set to gear ratio-disengaging position for controlling said valvular means for exhausting fluid pressure from said motor at a rategreater than the predetermined rate, whereby the rate of clutch engagement is substantially increased on disengagement of a desired gear ratio.

9. In a power transmission mechanism having a gear set and clutch, a member shiitable to establish either of a pair of gear shift ratios, fluid pressure means for controlling the movement of said member, a clutch controlling element, a

source of fluid pressure, a fluid motor for actuating said element, valvular means for controlling the flow of fluid pressure to and from said motor for efl'ecting clutch-disengaging and engaging movements of said element, and means responsive to fluid'pressure in said first named means for retarding the release of fluid pressure from-said motor. a v

10. In a control systemfor power tran mechanism having a gear set and clutch, a shiftable member for said gear set having neutral and gear ratio-establishing positions, fluid pressure control means for said member, clutch actuating and controlling mechanism, and means for reby the pressure in said flrst named means for changing said predetermined rate.

s'rnrmm Jor-msoN. Jr. 

